Five future No. 1 starters

Dylan Bundy, Taijuan Walker and other prospects who could turn into aces

Updated: May 2, 2012, 11:37 AM ET
By Kevin Goldstein | Baseball Prospectus
Dylan BundyAP Photo/Brian WesterholtDylan Bundy's hitless streak has the baseball world buzzing about the Orioles prospect.

With Bryce Harper and Mike Trout getting the call to the big leagues, Dylan Bundy is now the official engineer of the prospect hype train, and with good reason. The 19-year-old began the season with 13 no-hit innings and has struck out 25 of the 52 batters he has faced for low Class A Delmarva (Orioles), while allowing just three to reach base. This performance has produced the inevitable questions, especially on Twitter, regarding whether or not Bundy can become a No. 1 starter. However, becoming a No. 1 starter takes more than just stuff and command. It takes something that is more than a bit ineffable.

To be clear, "No. 1 starter" is a scouting/industry term, not a slot in the rotation. There were plenty of No. 3 starters taking the bump on Opening Day. There are 10 or fewer No. 1 starters in baseball. It takes stuff and command, but also durability, consistency and that extra something else.

"The label is the ultimate of the ultimate, and there's nothing wrong with a strict standard," an American League executive said. "I never project a prospect as anything more than a No. 2 starter for a reason. You're not a No. 1 until you actually prove over a period of time that you are a No. 1 in the big leagues. You cannot be anointed by a scouting report."

An AL scout echoed that sentiment: "The radar gun can't tell you who is going to be a No. 1. We envision guys in the mid-90s with crippling breaking balls and physicality, but at the end of the day, guys like Justin Verlander or Pedro Martinez become No. 1's at the major league level. Until you are pitching in the big leagues and putting away Cabrera and Fielder back-to-back, you're not a No. 1."

As for the extra component, people in the industry have trouble explaining it, but they know it when they see it.

"No. 1 guys are the guy where every time they take the mound, you feel you are going to win," another executive explained. "Every time out, you are going to get a defined area of performance. Good starters will give you average starts half of the time, and then be really good 25 percent of the time and bad the other 25 percent. A No. 1 is giving you 50 percent elite starts, 25 percent really good and 25 percent average. When you see Verlander get hit hard by the Yankees, you know he's going to deal the next time out. That's a No. 1. When you see Sabathia going late in the season for the Brewers on three days rest and pitching them into the playoffs, that's a No. 1. Most starters can't do that."

So while Bundy certainly has the makings for being a No. 1, he's far from joining that exclusive club.

"The hyperbole is justified," said a scout who has seen Bundy since his high school days. "His stuff and makeup are off the chart, and what he's doing to start a professional career might be unprecedented. But it's a long journey from Delmarva to No. 1."

Not only are No. 1 starters rare, but so are prospects with even the chances to even be a No. 1 starter. When asked how many potential No. 1's are in the minor leagues, the answers ranged from five to 15.

"There have been plenty of guys who looked like No. 1 starters in the minors or in the draft, and we've ended up with far more three, four, five starters or relievers than ones," said a National League exec.

"Whoever takes [Stanford right-hander] Mark Appel in June is going to have a press conference, and they are going to say he has a good chances to be a No. 1 starter," added an American League assistant GM. "And he does. But if we only have 10 or so of them in the big leagues, what really are the chances?"

Understanding the rarity and the unlikeliness that any pitcher will become a No. 1 starter, here are five pitching prospects who the industry sees as having the best chance, ranked in order of likelihood of becoming bona fide aces.

1. Taijuan Walker, RHP, Seattle Mariners (Double-A Jackson)

For many in the industry, Bundy's performance hasn't even been the most impressive by a pitcher in the minors. Consider Walker, who has a 1.64 ERA in four starts while striking out 26 in 22 innings and limiting the Southern League to a .203 batting average. Those numbers certainly aren't as gaudy as Bundy's, but Walker is doing it at Double-A, and he's just three months older than the Orioles' prize pitcher.